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Cold War Radar

Introduction to the Line

Radar Lines

1957 image of the radar lines in Canada.  Note the Mid-Canada Line in the centre

The Mid-Canada Line, or the MCL, was thought up by McGill University, which is why it was also called the McGill Fence.  It was first considered in the very early 1950s but not seriously until late 1953.

The MCL followed the Pinetree Line, construction beginning early in 1955.  It was created to deal with quicker planes and to give more warning time on top of the Pinetree Line.  It gave 300-60 000 feet cover and would allow North American planes to meet the bomber in the air. 

Running along the 55th parallel, Canada designed it and took on all costs.

It used an alarm so someone was not always there watching the radar.  It used typical radar but also Doppler radar which was based on the Doppler effect.  This basically meant that the frequency would be altered when something was between the stations.

The Line ran from Hopedale, Labrador to Dawson Creek, British Columbia, and there were 90 doppler detection stations and 8 section control stations.  The stations were actually located on two lines between 5-10 miles apart.

The Doppler stations were spread around 65 miles apart and provided better tracking and identification of where the aircraft was going and how fast.  Though the doppler sites were not staffed,  they had quarters for when personnel came to work on them.  The control sites were staffed.

There were controversies around the Line.  For example, Minister Howe wanted to support private enterprise over the government.  Bell were the managers of the system but had no actual control, rather it was given to a Crown corporation, Defence Construction. 

There was some poor organization surrounding it as well and as shown when they allowed bidding for diesel generators.  A British manufacturer won it, but they did not pay to have the parts shipped.  Therefore, Canada had to use Superconstellations, one of the biggest planes, and move them to Canada.

The MCL did cover some of the same area as the Pinetree Line.  And even while it was still being created the Dew Line was begun to extend coverage north.  It opened May 1957 (completely on January 1, 1958), but was already shut down by 1965.